1. Field of the Invention
The present invention is directed to a lid for an exothermic reaction mold device. In particular, the present invention is directed to a lid for an exothermic reaction mold device having a top opening for ignition and a front or side vent for releasing products of combustion.
2. Prior Art
Exothermic reaction welding is a known procedure for joining connectors such as, but not limited to, stranded metal cable to each other and also to ground rods and other parts. A wide variety of connectors may be made, such as, but not limited to, copper-to-copper or copper-to-steel. In the known exothermic reaction welding procedures, a mold, which may be composed of graphite, ceramic or other refractory material, contains an internal crucible into which a powder material is placed. At the bottom of the internal crucible is a shoulder which forms a seat for a metal retainer disk which supports the exothermic powder material.
The powder material may be composed of metal oxide such as tin oxide fines or copper or iron oxide fines. In one known procedure, the reduction of copper oxides is performed by aluminum which produces molten copper and aluminum oxide slag. When the powder is ignited, an exothermic reaction results in the crucible. The powder liquifies and the molten material melts the small steel or metal disk which is initially placed at the bottom of the crucible, thus permitting the molten metal to flow through a tap hole or passageway into a weld cavity. The molten copper is denser than the slag and separates from the slag and flows to the bottom of the cavity.
A hinged lid is not required for the exothermic reaction but is often utilized to contain the reaction. The lid will permit escape of gases produced during the exothermic reaction without danger of having the gases, flames or particles projecting outward.
Often times a portion of the powder material or a separate starting powder material will be sprinkled near an opening.
A spark or ignition gun is often used to start the exothermic reaction, since the exothermic reaction takes place extremely quickly once ignited. It is desirable to protect the spark or ignition gun for the projecting gases and flames to promote longevity of the spark or ignition gun.
Often, the weld will be made in the field in small, confined spaces such as a trench. It is also desirable to provide a lid and exothermic reaction lid which may be ignited from the top rather than the side for use in small, confined spaces.
Various other types of covers or lids have been proposed in the past. Moore et. al. (U.S. Pat. No. 5,145,106) discloses a hinged cover 42 which may include a two part filter system 43 to resist molten metal splatter from the exothermic reaction. Fuchs (U.S. Pat. No. 5,829,510) discloses an alternate lid design.
There remains a need for a lid for an exothermic reaction welding mold device which will promote the life of the mold and promote ease of lighting or ignition.
There remains a need for a lid for an exothermic reaction welding device which reduces weld splatter, including splatter on mold handles.
In addition, there remains a need for an exothermic reaction mold device which promotes the life of the spark or ignition gun.
The present invention is directed to a lid for an exothermic reaction mold device. The lid includes an upper or top face with an opening therethrough. The lid also includes a bottom or lower face with an opening therethrough. The top face and the lower face are joined by side faces with the upper face being parallel to the lower face. The opening through the upper or to face has an axis which passes through the opening of the lower face. In one embodiment, the lid is perpendicular to the axis of the circular opening.
A space between the upper face and the lower face of the lid forms a pocket in communication with both the circular opening of the top face and the elongated opening of the bottom face. The space is vented through a vent in one of the side faces. Accordingly, the vent forms a pocket which is recessed from a side face of the lid.
This invention will increase ease of ignition, prolong flint gun life, and reduce weld splatter coming from the crucible which will, in turn, increase the life of mold handles.